There is a brilliant and touching preface by Francisco Goldman that I highly recommend. The book itself, however, is dull. Returning to Pinochet's Chile to produce a clandestine film about the horrors of the dictatorship. the narrator, Miguel Littín, is horrified to learn that Pinochet's Chile (in 1985) was essentially calm (if slightly bullied) and prosperous modern country -- even during the State of Siege.
Having been in Spain during the Franco years, I can attest that the presence of the Guardia Civile were was merely like an unnoticed backdrop -- no different that what one would find in a modern American city today, except that they wore funny hats and carried those funny little machine guns.
Violeta Parra: http://www.youtube.com/watch?v=NcaSPaW6YdY&feature=fvst
Here - on a rec. from a friend is another version: